Battery electric vehicles (BEVs) continuously discharge the traction battery during operation and are not recharged during operation. This continuous discharge of the traction battery in a BEV is commonly referred to as charge-depleting mode. BEVs are normally connected to an external electric power source to recharge the traction battery after depletion. Hybrid electric vehicles (HEVs) are capable of operating in at least two modes; an all-electric mode (charge-depleting mode) and hybrid-vehicle mode (charge sustaining mode). As HEVs are operated in charge-depleting mode, the traction battery is continuously discharged until the traction battery reaches a state of charge in which the vehicle is transitioned to charge sustaining mode. In charge sustaining mode, the vehicle's internal combustion engine and regenerative braking are available to recharge the traction battery or maintain a minimum state of charge. Upon reaching a sufficient state of charge, the HEV may transition back to charge-depleting mode. Plug-in hybrid electric vehicles (PHEVs) have the capability to operate in at least two modes as an HEV, but also have the ability to recharge the traction battery via an external power source. PHEVs use as much pre-saved battery energy as possible until the next battery charge event. After the battery state of charge decreases to a predefined level, the PHEV resumes operation as an HEV in charge sustaining mode.